Three people, including the suspected assailant, have been killed in a shooting at a factory near the Swiss city of Lucerne, police said on Wednesday.
Seven others were injured in the attack which happened just after 9 a.m. (0800 GMT) at a wood processing company in the town of Menznau, west of Lucerne, the police said in a statement.
Emergency services were at the scene and the area had been cordoned off. A news conference is due at 2 p.m. (1300 GMT).
Last month, a gunman killed three women and injured two men in the Swiss village of Daillon, stirring a debate about Switzerland's firearm laws that allow men to keep guns after their mandatory military service.
There is no national gun register but some estimates indicate that at least one in every three of Switzerland's 8 million inhabitants keeps a gun, many stored at home. Citizens outside the military can apply for a permit to purchase up to three weapons from the age of 18 in a country where sharp shooting and hunting are popular sports.
A shooting in the Zug regional parliament in 2001, in which 14 people were killed, prompted calls to tighten laws, but the majority of Swiss citizens rejected a proposal in 2011 for extra measures such as lock-ups for guns outside service periods.